I will try to above tests tomorrow. For what it's worth, changing MTU had no impact. I was out of the office today at another site on a open (no security) 802.11g wifi and had the same problems I'm having at work. Oddly, I don't seem to have this issues at home. But then at home I really don't use XP much at all. I'll report the results tomorrow. This is very, very easy for me to reproduce.